Insulating material



-' this material is in the form of plate-like greatly improves the quality of the insulatmaterials are not satisfactory for such Work,

40' minum magnesium silicate. It is found in mica-like form and when moderately heated, it puffs to about fifteen times its original UNITED STATES PATENT OFFICE ARTHUR J. RUSS, OF OAKDALE, PENNSYLVANIA, ASSIGNOR TO ARMSTRONG CORK COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA INSULATING MATERIAL No Drawing. Application filed May 8, 1926. Serial No. 107,790.

a surface bond with the material, and provides a block of high structural strength.

A desired formula is as follows:

This invention relates to insulating material and particularly to an insulating material formed from diatomaceous earth.

Insulating material of this character is geifling usually made up into blocks which may be iatomaceous earth 3,? used for various purposes. The usual mix Jefi-erisite comprises diatomaceous earth, hydrated lime Hydrated-lime and a small amount of a suitable material such as asbestos.

I have found that an insulating block of highly desirable characteristics may be obtained by adding to the mix an aggregate material which forms a surface bond with the lime and diatomaceous earth. Preferably An asbestos which will withstand high tiziegnperature, such as African brown It will be noted that the diatomaceous earth and the hydrated lime are used in substantially equal amounts. The proportions, may of course be varied, but I prefer to use 80 more than about ten percent hydrated lime or diatomaceous earth. The African fibre is of value in strengthening the block. For a high temperature block it is preferable to Hie an African fibm that fis, either a(-j bl 1 1 rg or an amgsite, in pre erence to ana dian or American fibres, Analysis sdiofi'vs that the African fibres contain a large amount of ferric or ferrous oxides, and a relatively small amountpicgmbined water, while the Canadian d the American res conta 1 erably greater quantity ofv combined water, a relatively small amount of ferric oxide and generally no ferrous oxide whatever. fibres are far more desirable in mixes for blocks to be used at high temperatures, but it will be understood that the other fibres may be used in blocks manufactured according to my invention and used for other puras they come in relatively small sizes, poses. Instead of using hydrated lime, whereas blocks made from my new material uicklime may be employed if desired. Other mag be made very large. alkaline earths, such as magnesium may be s above stated, jefierisite is one 0 he employed. vermiculite group and chemically is an alu- A block made from the above formula is a little lighter than he ordinary diatomaceous earth block, but instead of the chalky white appearance of the ordinary block, it has a slight color and the jeiferisite employed in the mix shows up throughout the mix as, 9%

particles, such as may be secured by utilizing a micaceous material. More specifically I prefer to use a mica of the vermiculite oup, such as 'efi'erisite. This materlal is found in large deposits and the chief characteristic of the material is that when fit1 ishrggtil to a moderate temperature it ex 0 ia es giving rise to very light wei ht pl'mrticles, which are highly desirable in a mixof this character.

The use of suchan aggregate material ing blocks. The ordinary diatomaceous earth block begins to check at about 1000 F. and crumbles at a somewhat higher temperature. There is a demand for an insulating block capable of standing up to about 2000 F. for use around steam boilers, oil refineries and the like. The ordinary calcined volume. It is the puffed-up jeiferisite which Tuse m mix. I have foun that it forms On this account the African 75 Llie ordinar golden brown particles. The block will with r d.mueriallr..higherfeiunerat block g it hout checking or cracking, an is'tlierefore capable of far more extended and severe uses. Another advantage of my improved block is the fact that it is better adapted for commercial handling than the ordinary diatomaceous earth block. It can be sawed, and subjected to other manufacturing processes, and experience shows that the amount of breakage and cracking during manufacture is materially smaller than in the case of the ordinary blocks. On this account my improved block has advantages over the usual block other than the fact that it is also capable of withstanding higher temperatures.

The block may be made up in the ordinary way by mixing themaferials Witl1 flfli l, 9, running the mud into molds and S11 ect1ng the blocks thus formed'to steam induration.

I have used the term Wlii'ifiiti term of general definition and not of limitation, and intend thereby to include not only rectangular blocks, but also specially shaped articles, such as pipe covering, still and boiler covers, insulating discs for electrical apparatus, and the like.

I have described a preferred embodiment so of my invention, but it will be understood that it it not thus limited, as it may be otherwise embodied within the scope of the following claims:

I claim:

1. An insulating material comprising a mixture of an alkaline earth, diatomaceous earth and an exfoliated vermiculite mineral. An insulating material comprising a mixture of an alkaline earth, diatomaceous earth and exfoliated jefferisite.

3. An insulating material comprising exfoliated jetferisite and a diatomaceous earth mix.v

4. An insulating material comprising amixture of an alkaline earth, diatomaceous earth and an exfoliated vermiculite mineral, the alkaline earth constituting more than about 10% of the mix.

5. An insulating material comprising a mixture of an alkaline earth, diatomaceous earth and an exfoliated vermiculite mineral, the alkaline earth and the diatomaceous earth being in substantially equal amounts.

6 An insulating material comprising a mixture of an alkaline earth, diatomaceous earth, an exfoliated vermiculite mineral and an asbestos which will Withstand high temperatures. a

7. An insulating material comprising a mixture of an alkaline earth, diatomaceous earth, an exfoliated vermiculite mineral and a fibrous material.

8. An insulating material comprising a mixture of an alkaline earth, diatomaceous earth and an exfoliated vermiculite mineral,

resent in an t e other mathe vermiculite mineral bein amount which is in excess 0 terials comprising the mix.

9. An insulating material comprising about 27% by weight of diatomaceous earth and about the same amount of an alkaline earth, substantially all of the remainder of the block being an exfoliated vermiculite mineral.

10. Aninsulating material comprising a mixture of about 27% by weight of diatoma ceous earth, about 27% of an alkaline earth and about 4% of an asbestos which will withstand a high temperature, substantially all of the remainder of themix being an exfoliated vermiculite mineral.

11. An insulating material comprising about 40% of an exfoliated vermiculite mineral, substantially all of the remainder of the about 40% of an exfoliated vermiculite mineral, substantially all of the remainder of the mix being diatomaceous earth and an alkaline earth in equal amounts, the mixture also having a small amount of fibrous material.

13. An insulating material comprising a mixture of about 27% by weight of diatomaceous earth, about 27% of a hydrated alkaline earth and about 4% of a fibrous material, substantially all of the remainder of thelmix being an exfoliated vermiculite minera 14. An insulating material comprising a mixture of lime, an exfoliated material of the vermiculite grou diatomaceous earth and a fibrous materia 15. The process of forming an insulating block which consists in mixing a. diatomaceous earth, exfoliated vermiculite, and lime, molding the mix, and subjecting th blocks to steam induration.

16. The process of forming an insu ting block which consists in mixing a diatomaceous earth, an exfoliated vermiculite, a fibrous material, an alkaline earth bonding material, molding the mix, and subjecting the block to steam induration.

17. A heat insulating material which includes vermiculite material, diatomaceous earth and a binder.

In testimony whereof I have hereunto set my hand.

ARTHUR J. RUSS. 

